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Python 3.9.0a6

Release Date: April 28, 2020

This is an early developer preview of Python 3.9

Python 3.9 is still in development. This release, 3.9.0a6 is the last out of six planned alpha releases. Alpha releases are intended to make it easier to test the current state of new features and bug fixes and to test the release process. During the alpha phase, features may be added up until the start of the beta phase (2020-05-18) and, if necessary, may be modified or deleted up until the release candidate phase (2020-08-10). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Major new features of the 3.9 series, compared to 3.8

Many new features for Python 3.9 are still being planned and written. Among the new major new features and changes so far:

  • PEP 584, Union Operators in dict
  • PEP 585, Type Hinting Generics In Standard Collections
  • PEP 593, Flexible function and variable annotations
  • PEP 602, Python adopts a stable annual release cadence
  • PEP 616, String methods to remove prefixes and suffixes
  • PEP 617, New PEG parser for CPython
  • BPO 38379, garbage collection does not block on resurrected objects;
  • BPO 38692, os.pidfd_open added that allows process management without races and signals;
  • BPO 39926, Unicode support updated to version 13.0.0;
  • BPO 1635741, when Python is initialized multiple times in the same process, it does not leak memory anymore;
  • A number of Python builtins (range, tuple, set, frozenset, list, dict) are now sped up using PEP 590 vectorcall;
  • A number of Python modules (_abc, audioop, _bz2, _codecs, _contextvars, _crypt, _functools, _json, _locale, operator, resource, time, _weakref) now use multiphase initialization as defined by PEP 489;
  • A number of standard library modules (audioop, ast, grp, _hashlib, pwd, _posixsubprocess, random, select, struct, termios, zlib) are now using the stable ABI defined by PEP 384.

  • (Hey, fellow core developer, if a feature you find important is missing from this list, let Ɓukasz know.)

The next pre-release, the first beta release of Python 3.9, will be 3.9.0b1. It is currently scheduled for 2020-05-18.

More resources

And now for something completely different

Scientist (Graham Chapman): Standard IQ tests gave the following results. The penguins scored badly when compared with primitive human sub-groups like the bushmen of the Kalahari but better than BBC program planners.
Scientist: These IQ tests were thought to contain an unfair cultural bias against the penguin. For example, it didn't take into account the penguins extremely poor educational system. To devise a fairer system of test, a team of our researchers spent eighteen months in Antarctica living like penguins, and subsequently dying like penguins - only quicker - proving that the penguin is a clever little sod in his own environment.

Full Changelog


Version Operating System Description MD5 Sum File Size GPG
Gzipped source tarball Source release 24b42e49de0fa90d77527d48cfe440ad 24457620 SIG
XZ compressed source tarball Source release 6b5d9b7fcbc7d3a79217bb1587bae16e 18202376 SIG
macOS 64-bit installer macOS for OS X 10.9 and later b8c250a9da032892be257405dd4cb703 29598507 SIG
Windows help file Windows 9139f19f1c54e4e0c47192ba826d4b67 8735047 SIG
Windows x86-64 embeddable zip file Windows for AMD64/EM64T/x64 0f3d9873584010b3bd828c221bf46bc6 8318514 SIG
Windows x86-64 executable installer Windows for AMD64/EM64T/x64 cb64b6a226410657bfa7d25a0cd0b311 28187208 SIG
Windows x86-64 web-based installer Windows for AMD64/EM64T/x64 8652b1f7522972f04ec38f3bfa938341 1364120 SIG
Windows x86 embeddable zip file Windows 51d266336d94d3aa2c6c2e03fa48150f 7520451 SIG
Windows x86 executable installer Windows b5d7ea15620fae14cfb7e65f5156fb5b 27132344 SIG
Windows x86 web-based installer Windows 7719192c8351a76a6569f2bc79d1216b 1325808 SIG